Question

Which two types of reactions are also always redox reactions? Explain your answer.

Answer 1

Answer : The two types of reactions always redox reaction are, Single-displacement reaction and Disproportionation reaction.

Explanation :

Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.

Single-displacement reaction : It is a type of reaction in which the most reactive element displaces the least reactive element from its compound.

It is type of redox reaction where a species simultaneously oxidized and reduced and form different products.

For example : $Mg+CuSO_4\rightarrow MgSO_4+Cu$

In this reaction, oxidation takes place when $Mg$ lose electrons and form  $Mg^{2+}$ and reduction takes place when $Cu^{2+}$ gain electrons and form $Cu$.

Disproportionation reaction : It is a type of chemical reaction in which a molecule is converted or transformed into two or more different products.

It is type of redox reaction where a species simultaneously oxidized and reduced and form different products.

For example : $2H_2PO_4^-\rightarrow HPO_4^{2-}+H_3PO_4$

In this reaction, oxidation and reduction reaction takes palace simultaneously by the one species that is, $H_2PO_4^-$.

In this reaction, oxidation takes place when $H_2PO_4^-$ lose electrons and form $HPO_4^{2-}$ and reduction takes place when $H_2PO_4^-$ gain electrons and form $H_3PO_4$.

Hence, the two types of reactions always redox reaction are, Single-displacement reaction and Disproportionation reaction.

Answer 2

Single displacement and combustion reactions are ALWAYS redox.